View source for Standby power

{{Short description|Consumption of energy by electrical devices while switched off or in standby mode}}
{{For|systems that provide auxiliary power|Emergency power system}}
{{Redirect|Phantom load|microphone powering technique|Phantom power}}
{{Redirect|Idling current|transistor quiescent current|Biasing}}
{{Redirect|Electricity vampire|circuits consuming all of a battery's charge|Battery vampire}}
{{Redirect|Vampire load|the safety discharging resistor|Bleeder load}}
{{distinguish|Leakage (electronics)}}

'''Standby power''', also called '''vampire power<ref>{{cite web |title=Vampire Power - The Ghost In The Machine |url=https://powerdensity.com/vampire-power-the-ghost-in-the-machine/ |website=Silanna Semiconductor |date=7 September 2021 |ref=vampirepower}}</ref>''', '''vampire draw''', '''phantom load''', '''ghost load,''' or '''leaking electricity,''' refers to how certain electronic and electrical appliances consume electricity while they are not actively in use, but which are still plugged in to mains while in [[sleep mode|standby mode]]. It only occurs because some devices claim to be "switched off" on the electronic interface but are actually in a different state (standby mode) such as to power a clock or allow for remote control power-on. 

The term is also used for power [[Power supply|power adapter]]s plugged in to mains but not connected to any electronic device. They will still consume a small amount of power despite not powering an electronic device, which is sometimes called [[no-load power]]. 

For all electronic devices or power adapters that  consume standby power, just turning off the plug or power brick (where possible) or disconnecting it from the power point (mains) can completely solve the problem of standby power consumption. Having a mains outlets with power switches or a power strip with a power switch eliminates the need to disconnect all devices from the power-point. 

In the past, standby power was primarily a non-issue for users, electricity providers, manufacturers, and government regulators. In the twenty-first century's first decade, awareness of the issue grew, becoming essential for all parties. Up to the middle of the decade, standby power was often several watts or tens of watts per appliance. By 2010, regulations were in place in most developed countries restricting standby power of devices sold to one watt (and half that from 2013).

==Definition==
Standby power is electrical power used by appliances and equipment while switched off or not performing their primary function, often waiting to be activated by a [[remote control]]ler. That power is consumed by internal or external power supplies, remote control receivers, text or light displays, and circuits energized when the device is plugged in, even when switched off.<ref name=lblfaq/>

While this definition is inadequate for technical purposes, there is no formal definition; an international standards committee is developing a definition and test procedure.<ref name=lblfaq>{{Cite web |url=https://standby.lbl.gov/frequently-asked-questions|title=US Lawrence Berkeley National Laboratory, Frequently-asked questions |access-date=2024-09-01 }}</ref>

The term is often used more loosely for any device that continuously must use a small amount of power even when not active; for example, a telephone answering machine must be available at all times to receive calls, and switching off to save energy is not an option. Timers, powered [[Thermostat|thermostats]], and the like are other examples. An [[uninterruptible power supply]] could be considered to waste standby power only when the computer it protects is off. Properly disconnecting standby power is, at worst, inconvenient; powering down completely, for example, an answering machine not handling a call, renders it useless.

==Advantages and disadvantages==

===Advantages===
Standby power is often consumed for a purpose, although in the past there was little effort to minimize power used.
*It may enable a device to switch on very quickly without delays that might otherwise occur ("[[instant-on]]"). It was used, for example, with [[cathode-ray tube|CRT]] television receivers (now supplanted mainly by flat screens), where a small current was passed through the tube heater, avoiding a delay of many seconds in starting up.
*It may be used to power a remote control receiver so that when infrared or [[Radio frequency|radio-frequency]] signals are sent by a remote control device, the equipment can respond, typically by changing from standby to fully on mode.
*Standby power may be used to power a display, operate a clock, etc., without switching the equipment to full power.
*Battery-powered equipment connected to [[mains electricity]] can be kept fully charged although switched on; for example, a mobile telephone can be ready to receive calls without depleting its battery charge.
*It enables devices to either turn on or off into a standby state automatically without human intervention (for example, a timer or [[Wake-on-LAN]]).

===Disadvantages===
The disadvantages of standby power mainly relate to the energy used (each watt of continuous standby consumes about 9 kWh of electricity per year.) and the cost thereof.  Devices often used ten watts or more before adopting the [[One Watt Initiative]].

==Magnitude==
Standby power makes up a portion of homes' [[miscellaneous electric load]], including small appliances, security systems, and other small power draws. The U.S. Department of Energy said in 2008:
<blockquote>
"Many appliances continue to draw a small amount of power when they are switched off. These "phantom" loads occur in most appliances that use electricity, such as VCRs, televisions, stereos, computers, and kitchen appliances. This can be avoided by unplugging the appliance or using a power strip and using the switch on the power strip to cut all power to the appliance."<ref>US Department of Energy, [http://www1.eere.energy.gov/consumer/tips/home_office.html "Home Office and Home Electronics,"] {{webarchive|url=https://web.archive.org/web/20090825001908/http://www1.eere.energy.gov/consumer/tips/home_office.html |date=2009-08-25 }} 15 Jan 2008, Accessed on: 7 May 2008.</ref>
</blockquote>

Standby power used by older devices can be as high as 10–15&nbsp;W per device,<ref>{{cite journal
 | title = Energy cost of PCs on standby
 | publisher = London: BBC 7
 |date=April 2006
 | url = http://news.bbc.co.uk/1/hi/programmes/click_online/4929594.stm
 | access-date = 2006-08-09}}</ref> while a modern [[High-definition television|HD]] [[LCD television]] may use less than 1&nbsp;W in standby mode. Some appliances use no energy when turned off. Many countries adopting the [[One Watt Initiative]] now require new devices to use no more than 1&nbsp;W starting in 2010 and 0.5&nbsp;W in 2013.

Although the power needed for functions such as displays, indicators, and remote control functions is relatively small, the large number of such devices and their continuous plugging in resulted in energy usage before the One Watt regulations of 8 to 22 percent of all appliance consumption in different countries, or 32 to 87 W.  This was around 3–10 percent of total residential consumption.<ref>{{cite web |title=Standby power – you're paying for it |url=http://www.energy.unsw.edu.au/NewsInfoStandbyPower.shtml |publisher=University of New South Wales |archive-url=https://web.archive.org/web/20120223230214/http://www.energy.unsw.edu.au/NewsInfoStandbyPower.shtml |archive-date=2012-02-23 |date=2009}}</ref> In 2004, standby modes on electronic devices accounted for 8% of all British residential power.<ref>{{Cite web|url = http://www.berr.gov.uk/files/file31890.pdf|title = Energy review 2006, Department of Trade and Industry, UK|archive-url = http://webarchive.nationalarchives.gov.uk/20090609003228/http://www.berr.gov.uk/files/file31890.pdf|archive-date = 2009-06-09}}</ref> A similar study in France in 2000 found that standby power accounted for 7% of total residential consumption.<ref>{{Cite web|url = http://standby.lbl.gov/ACEEE/StandbyPaper.pdf|title = Standby Power Use: How Big is the Problem? What Policies and Technical Solutions Can Address It?|archive-url = https://web.archive.org/web/20070706120640/http://standby.lbl.gov/ACEEE/StandbyPaper.pdf|archive-date = 2007-07-06}}</ref>

In 2004, the California Energy Commission produced a report containing typical standby and operational power consumption for 280 household devices, including baby monitors and toothbrush chargers.<ref name=devtest/>

In 2006, some electronics, such as microwaves, CRTs, and VHS players, used more standby power than appliances manufactured in the previous five years.<ref name=econ>[http://www.economist.com/displaystory.cfm?story_id=5571582 Pulling the plug on standby power], Mar 9, 2006, [[The Economist]]</ref>

In the US the average home used an average of 10,649&nbsp;kWh of electricity per year in 2019, down from 11,040&nbsp;kWh in 2008.<ref>{{cite journal
 | title = How much electricity does an American home use
 | publisher = U.S. Energy Information Administration
 | date=October 2020
 | url = https://www.eia.gov/tools/faqs/faq.php?id=97&t=3
 | access-date = Dec 3, 2020}}</ref><ref>{{cite journal
 | title = Frequently Asked Questions – Electricity
 | publisher = U.S. Energy Information Administration
 | date=Jun 2010
 | url = http://www.eia.doe.gov/ask/electricity_faqs.asp#electricity_use_home
 | access-date = Jan 6, 2011
 | archive-url = https://web.archive.org/web/20100602235850/http://www.eia.doe.gov/ask/electricity_faqs.asp
 | archive-date = Jun 2, 2010}}</ref> Each watt of power consumed by a device running continuously consumes about 9&nbsp;kWh (1&nbsp;W × 365.25&nbsp;days/year × 24&nbsp;hours/day) per year, a little less than one thousandth of the annual US household consumption. Unplugging a device constantly consuming standby power saves a yearly 9&nbsp;kWh for each watt of continuous consumption (saving $1 per year at average US rates<ref>{{Cite web|title = The Price Of Electricity In Your State| website=NPR | date=28 October 2011 |url = https://www.npr.org/sections/money/2011/10/27/141766341/the-price-of-electricity-in-your-state|access-date = 2015-08-01| last1=Jiang | first1=Jess }}</ref>).

Devices such as security systems, fire alarms, and [[digital video recorders]] require continuous power to operate properly (though in the case of electric timers used to disconnect other devices on standby, they actually reduce total energy usage). The [[#Reducing_standby_consumption|Reducing Consumption section below]] provides information on reducing standby power.

==Fire risks==
There is a risk of fire from devices in standby mode. Televisions, in particular, have been reported to catch fire in standby mode.<ref>{{cite journal
 |title       = Causes of fires involving television sets in dwellings.
 |publisher   = London: Department of Trade and Industry
 |date        = April 2001
 |url         = http://www.dti.gov.uk/homesafetynetwork/pdf/tvdetail.pdf
 |access-date  = 2006-08-09
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20060216131414/http://www.dti.gov.uk/homesafetynetwork/pdf/tvdetail.pdf
 |archive-date = 2006-02-16
}}</ref>

Before the development of modern semiconductor electronics, it was not uncommon for devices, typically television receivers, to catch fire when plugged in but switched off,<ref>[https://news.google.com/newspapers?nid=1298&dat=19740429&id=3N9NAAAAIBAJ&sjid=CIsDAAAAIBAJ&pg=1886,256339 Free Lance-Start newspaper, 29 April 1974]"Unplug the TV set before going to bed"</ref> sometimes when fully switched off rather than on standby. This is much less likely with modern equipment, but not impossible. Older [[cathode-ray tube]] display equipment (television and computer displays) had high voltages and currents and were far more of a fire risk than thin-panel LCDs and other displays.

Contributing factors for electrical fires include:
* Damp environments
* [[Lightning]] strikes affecting building wiring
* Age of the appliance—older appliances are less well designed for safety, and may have deteriorated

==Policy==
{{Further | One Watt Initiative}}
The [[One Watt Initiative]] was launched by the [[International Energy Agency|IEA]] in 1999 to ensure through international cooperation that by 2010 all new appliances sold in the world only use one watt in standby mode. This would reduce CO<sub>2</sub> emissions by 50 million tons in the OECD countries alone by 2010.

In July 2001 [[United States|U.S.]] President [[George W. Bush]] signed an [[Executive order (United States)|Executive Order]] directing federal agencies to "purchase products that use no more than one watt in their standby power consuming mode".<ref name=USExecutiveOrder>[https://georgewbush-whitehouse.archives.gov/news/releases/2001/07/20010731-10.html Executive Order – Energy Efficient Standby Power Devices], July 2001, [[The White House]]</ref>

In July 2007 California's 2005 appliance standards came into effect, limiting external power supply standby power to 0.5 watts.<ref>{{cite web |url=http://www.fypower.org/news/?p=1386 |title=Flex Your Power Energy News - Power Plug » California Slays "Energy Vampires"; More Stringent Regulations Took Effect July 1 |access-date=2010-09-16 |url-status=dead |archive-url=https://web.archive.org/web/20110209212259/http://www.fypower.org/news/?p=1386 |archive-date=2011-02-09 }}</ref>

On 6 January 2010, the [[European Commission]] (EC) [[Regulation No 1275/2008]] came into force. The regulations mandate that from 6 January 2010, "off mode" and standby power for electrical and electronic household and office equipment shall not exceed 1W, and "standby plus" power (providing information or status display in addition to possible reactivation function) shall not exceed 2W. Equipment must, where appropriate, be provided in off mode or standby mode when the equipment is connected to the primary power source. These figures were halved on 6 January 2013.<ref>[https://web.archive.org/web/20111109020207/http://www.bis.gov.uk/assets/bispartners/nmo/docs/eup/leaflets/standby-and-off-leaflet.pdf BIS department, UK: Standby and off leaflet]</ref>

==Determining standby power==

===Identifying devices===
The following types of devices consume standby power.
* [[Transformer]]s for voltage conversion.
* [[Wall wart]] power supplies powering devices that are switched off.
* Many devices with "instant-on" functions that respond immediately to user action without warm-up delay.
* Commonly used LED strips and such low power household lights.
* Electronic and electrical devices in standby mode that can be woken by a remote control, e.g. some air conditioners, audio-visual equipment such as a [[television]] receiver
* Electronic and electrical devices that can carry out some functions even when switched off, e.g. with an electrically powered timer. Most modern [[computer]]s consume standby power, allowing them to be woken remotely (by [[Wake on LAN]], etc.) or at a specified time. These functions are always enabled even if not needed; power can be saved by disconnecting from mains (sometimes by a switch on the back), but only if functionality is not needed.
* [[Uninterruptible power supplies]] (UPS)

Other devices consume standby power required for normal functioning that cannot be saved by switching off when not used. For these devices, electricity can only be saved by choosing units with minimal permanent power consumption:
* Cordless telephones and answering machines
* Timers that operate devices
* Security systems and fire alarms
* Transformer-powered doorbells
* Programmable thermostats
* Motion sensors, light sensors, built-in timers and automatic sprinklers

===Estimating standby power===
Standby power consumption can be estimated using tables of standby power used by typical devices,<ref name=LBLMeasureHome>{{cite web | url = http://standby.lbl.gov/summary-table.html | title = Measuring Standby Power in Your Home | access-date = 2008-09-20 | archive-date = 2017-12-22 | archive-url = https://web.archive.org/web/20171222202444/http://standby.lbl.gov/summary-table.html | url-status = dead }}</ref> although standby power used by appliances of the same class vary extremely widely (for a CRT computer display standby power is listed at a minimum of 1.6&nbsp;W, maximum 74.5&nbsp;W). Total standby power can be estimated by measuring total house power with all devices standing by, then disconnected,<ref name=LBLMeasureHome /><ref>{{cite web |url=http://www.kouba-cavallo.com/phantom.html |title=Kouba-Cavallo Associates: Phantom Load Calculation |website=www.kouba-cavallo.com |url-status=dead |archive-url=https://web.archive.org/web/20011220042107/http://kouba-cavallo.com/phantom.html |archive-date=2001-12-20}}</ref> but this method is inaccurate and subject to large errors and uncertainties.<ref name=devtest/>

===Measuring standby power===

The power wasted in standby must go somewhere; it is dissipated as heat. The temperature, or perceived warmth, of a device on standby long enough to reach a stable temperature gives some idea of power wasted.

For most home applications, wattmeters give a good indication of energy used and some indication of standby consumption.

A [[wattmeter]] is used to measure electrical power. Inexpensive plugin wattmeters, sometimes described as energy monitors, are available from prices of around [[US$]]10. Some more expensive models for home use have remote display units.  In the US wattmeters can often also be borrowed from local power authorities<ref>[http://www.austinutilities.com/pages/residential_audit_watts.asp Austin Utilities – Residential – Home Energy Audit – Watts Up] {{webarchive|url=https://web.archive.org/web/20090312071207/http://www.austinutilities.com/pages/residential_audit_watts.asp |date=2009-03-12 }}</ref> or a local public library.<ref>{{Cite web |url=http://www.mge.com/home/saving/energymeter.htm |title=Portable Energy Meter |access-date=2008-03-13 |archive-date=2008-04-12 |archive-url=https://web.archive.org/web/20080412043957/http://www.mge.com/Home/saving/EnergyMeter.htm |url-status=dead }}</ref><ref>{{Cite web |url=https://wattsupmeters.com/secure/support.php?pn=12#q21 |title=Watts up? Support: FAQs<!-- Bot generated title --> |access-date=2008-03-13 |archive-date=2012-03-03 |archive-url=https://web.archive.org/web/20120303142605/https://wattsupmeters.com/secure/support.php?pn=12#q21 |url-status=dead }}</ref>  Although accuracy of measurement of low AC current and quantities derived from it, such as power, is often poor, these devices are nevertheless indicative of standby power,<ref name=ll>{{Cite web |url=http://standby.lbl.gov/measure.html |title=US Lawrence Berkeley National Laboratory, Standby Power, measuring standby |access-date=2011-09-21 |archive-date=2017-12-22 |archive-url=https://web.archive.org/web/20171222203620/http://standby.lbl.gov/measure.html |url-status=dead }}</ref> if sensitive enough to register it. Some home power monitors simply specify an error figure such as 0.2%, without specifying the parameter subject to this error (e.g., voltage, easy to measure), and without qualification.<ref>{{Cite web | url=http://www.p3international.com/products/special/P4400/P4400-CE.html | title=Kill a Watt Meter - Electricity Usage Monitor &#124; P3}}</ref> Errors of measurement at the low [https://www.elvistech.ng/product/solar-generator/ standby powers] used from about 2010 (i.e., less than a few watts) may be a very large percentage of the actual value—accuracy is poor.<ref name=ll/> Modification of such meters to read standby power has been described and discussed in detail (with [[oscilloscope]] waveforms and measurements).<ref>[http://www.eevblog.com/forum/projects/measuring-standby-power/ Measuring standby power]</ref> Essentially, the meter's shunt [[resistor]], used to generate a voltage proportional to load current, is replaced by one of value typically 100 times larger, with protective diodes. Readings of the modified meter have to be multiplied by the resistance factor (e.g. 100), and maximum measurable power is reduced by the same factor.

Professional equipment capable of (but not specifically designed for) low-power measurements clarifies typically that the error is a percentage of ''full-scale'' value, or a percentage of reading plus a fixed amount, and valid only within certain limits.

In practice, accuracy of measurements by meters with poor performance at low power levels can be improved by measuring the power drawn by a fixed load such as an incandescent light bulb, adding the standby device, and calculating the difference in power consumption.<ref name=ll/>

Less expensive wattmeters may be subject to significant inaccuracy at low current (power). They are often subject to other errors due to their mode of operation:
* If the load is highly [[Electrical reactance|reactive]], the power shown by some meters may be inaccurate. Meters capable of displaying power factor do not have this problem.
* Many AC meters are designed to give readings that are only meaningful for the sinusoidal waveforms of normal AC power. Waveforms for [[switched-mode power supplies]] as used in much [[electronic equipment]] may be very far from sinusoidal, causing power readings of such meters to be meaningless. Meters specified to read "RMS power" do not have this problem.
Laboratory-grade equipment designed for low power measurement, which costs from several hundreds of [[US dollar]]s and is much larger than simple domestic meters, can measure power down to very low values without any of these effects. The US [[Independent Electrical Contractors|IEC]] 62301 recommendation for measurements of active power is that power of 0.5&nbsp;W or greater shall be made with an uncertainty of 2%. Measurements of less than 0.5&nbsp;W shall be made with an uncertainty of 0.01&nbsp;W. The power measurement instrument shall have a resolution of 0.01&nbsp;W or better.<ref name=devtest>{{Cite web |url=http://www.energy.ca.gov/reports/2004-10-13_500-04-057.PDF |title=Developing and Testing Low Power Mode Measurement Methods, prepared by Lawrence Berkeley National Laboratory for California Energy Commission Public Interest Energy Research Program, 2004 |access-date=2011-10-11 |archive-date=2012-04-06 |archive-url=https://web.archive.org/web/20120406213530/http://www.energy.ca.gov/reports/2004-10-13_500-04-057.PDF |url-status=dead }}</ref><ref>[http://www.energystar.gov/ia/partners/prod_development/downloads/power_supplies/EPSupplyEffic_TestMethod_0804.pdf Test Method for Calculating the Energy Efficiency of Single-Voltage External Ac-Dc and Ac-Ac Power Supplies, funded by California Energy Commission, 2004]</ref>

Even with laboratory-grade equipment measurement of standby power has its problems. There are two basic ways of connecting equipment to measure power; one measures the correct voltage, but the current is wrong; the error is negligibly small for relatively high currents, but becomes large for the small currents typical of standby—in a typical case a standby power of 100&nbsp;mW would be overestimated by over 50%. The other connection gives a small error in the voltage but accurate current, and reduces the error at low power by a factor of 5000. A laboratory meter intended for measurement of higher powers may be susceptible to this error.<ref name=appnote102>[http://www.merestechnika.com/pdf-docs/zes_applicat_102_standby_power_e.pdf ZES Zimmer Application Note 102: Measurement of standby power and energy efficiency] {{webarchive|url=https://web.archive.org/web/20120426071139/http://www.merestechnika.com/pdf-docs/zes_applicat_102_standby_power_e.pdf |date=2012-04-26 }}</ref> Another issue is the possibility of measuring equipment damage if in a very sensitive range capable of measuring a few milliamps; if the device being measured comes out of standby and draws several amps, the meter can be damaged unless it is protected.<ref name=appnote102/>

<gallery>
Image:standby_indicator.jpg|Standby Indicator
File:Power supply1.jpg|DC Power adaptor
</gallery>

==Reducing standby consumption==

===Operating practices===

Some equipment has a quick-start mode; standby power is eliminated if this mode is not used.  Video game consoles often use power when they are turned off, but the standby power can be further reduced if the correct options are set.  For example, a [[Wii]] console can go from 18 watts to 8 watts to 1 watt by turning off the WiiConnect24 and Standby Connection options.<ref>{{cite journal
 | title = WiiConnect24
 | publisher = Nintendo
 | year = 2010
 | url = https://www.nintendo.com/consumer/systems/wii/en_na/settingsWiiConnect24.jsp#standby
 | access-date = Jan 6, 2011
 | journal = 
 | archive-date = December 31, 2010
 | archive-url = https://web.archive.org/web/20101231020617/http://www.nintendo.com/consumer/systems/wii/en_na/settingsWiiConnect24.jsp#standby
 | url-status = dead
 }}</ref><ref>{{cite journal
 | title = Having the Wii turned off but in Standby Mode
 | publisher = Nintendo Discussions
 | date = April 2010
 | url = http://techforums.nintendo.com/message/1997#1997
 | access-date = Jan 6, 2011
 | journal = 
 | archive-date = July 14, 2011
 | archive-url = https://web.archive.org/web/20110714184502/http://techforums.nintendo.com/message/1997#1997
 | url-status = dead
 }}</ref>

Devices that have rechargeable batteries and are always plugged in use standby power even if the battery is fully charged.  Corded appliances such as vacuum cleaners, [[electric razor]]s, and simple telephones do not need a standby mode and do not consume the standby power that cordless equivalents do.

Older devices with power adapters that are large and are warm to the touch use several watts of power.  Newer power adapters that are lightweight and are not warm to the touch may use less than one watt.

Standby power consumption can be reduced by unplugging or totally switching off, if possible, devices with a standby mode not currently in use; if several devices are used together or only when a room is occupied, they can be connected to a single [[power strip]] that is switched off when not needed. This may cause some electronic devices, particularly older ones, to lose their configuration settings.

[[Image:Socket 5.jpg|thumb|A switchable power strip or power bar]]

Timers can be used to turn off standby power to devices that are unused on a regular schedule. Switches that turn the power off when the connected device goes into standby,<ref>{{Cite web |url=http://www.nomorestandby.com/ |title=no the Standby Plug, a standby cut off switch from Scotland |access-date=2009-01-25 |archive-date=2008-11-20 |archive-url=https://web.archive.org/web/20081120035525/http://www.nomorestandby.com/ |url-status=dead }}</ref> or that turn other outlets on or off when a device is turned on or off are also available. Switches can be activated by sensors. [[Home automation]] sensors, switches and controllers can be used to handle more complex sensing and switching. This produces a net saving of power so long as the control devices themselves use less power than the controlled equipment in standby mode.<ref>{{Cite web |url=http://www.nomorestandby.com/faq.htm |title=the Standby Plug FAQ, accessed January 26, 2009 |access-date=January 25, 2009 |archive-date=October 4, 2009 |archive-url=https://web.archive.org/web/20091004191957/http://www.nomorestandby.com/faq.htm |url-status=dead }}</ref>

Standby power consumption of some computers can be reduced by turning off components that use power in standby mode. For instance, disabling [[Wake-on-LAN]] (WoL),<ref>[http://www.lesswatts.org/tips/ethernet.php LessWatts.org – Saving Power on Intel systems with Linux] {{webarchive|url=https://web.archive.org/web/20071126071350/http://www.lesswatts.org/tips/ethernet.php |date=2007-11-26 }}</ref> "wake on modem", "wake on keyboard" or "wake on USB" may reduce power when in standby. Unused features may be disabled in the computer's [[BIOS]] setup to save power.

Devices were introduced in 2010 that allow the remote controller for equipment to be used to totally switch off power to everything plugged into a power strip. It was claimed in the UK that this could save £30, more than the price of the device, in one year.<ref>{{Cite web |url=http://www.britishgas.co.uk/products-and-services/energy-savers/standby-power-savers/TV.html |title=Standby power saver—uses device remote control to power down equipment |access-date=2011-10-12 |archive-date=2011-10-02 |archive-url=https://web.archive.org/web/20111002160646/http://www.britishgas.co.uk/products-and-services/energy-savers/standby-power-savers/TV.html |url-status=dead }}</ref>

===Equipment efficiency===
As users of energy and government authorities have become aware of the need not to waste energy, more attention is being paid to the electrical [[efficiency]] of devices (fraction of power consumed that achieves functionality, rather than waste heat); this affects all aspects of equipment, including standby power. Standby power use can be decreased both by attention to circuit design and by improved technology. Programs directed at consumer electronics have stimulated manufacturers to cut standby power use in many products. It is probably technically feasible to reduce standby power by 75% overall; most savings will be less than a watt, but other cases will be as large as 10 watts.<ref>{{Cite web |url=http://standby.lbl.gov/faq.html |title=US Lawrence Berkeley National Laboratory, Frequently Asked Questions on Standby Power |access-date=2011-10-10 |archive-date=2017-07-11 |archive-url=https://web.archive.org/web/20170711175523/http://standby.lbl.gov/faq.html |url-status=dead }}</ref>

For example, a commercially available computer in [[Wake-on-LAN]] standby typically consumed 2&nbsp;to&nbsp;8 watts of standby power {{As of|2011|lc=on}}, but it was possible to design much more efficient circuitry: a purpose-designed microcontroller can reduce total system power to under 0.5&nbsp;watts, with the microcontroller itself contributing 42&nbsp;mW.<ref>{{Cite web |url=http://www.silabs.com/products/mcu/Pages/Wake-on-LAN.aspx |title=Silicon Labs: Low Power Wake-on-LAN Challenges and Solutions |access-date=2011-10-10 |archive-date=2011-08-30 |archive-url=https://web.archive.org/web/20110830105643/http://www.silabs.com/products/mcu/Pages/Wake-on-LAN.aspx |url-status=dead }}</ref>

==See also==
{{Portal|Energy}}

* [[Green computing]]
* [[List of energy storage projects]]
* [[Low-power electronics]]
* [[Miscellaneous electric load]]
* [[Losses in electrical systems#Parasitic_loss|Parasitic load]]
* [[AC adapter]]
* [[Losses in electrical systems]]

==References==
{{Reflist|30em}}

==External links==
* [http://standby.lbl.gov/ Standby Power Home Page], [[Lawrence Berkeley National Laboratory]]
* [http://www.energystar.gov/ Official Energy Star Website], [[Energy Star]]
* [http://www.energymanagertraining.com/StandbyPower/main.htm International Conference on Standby Power, New Delhi INDIA]
* [http://www.wagonmaker.com/chapter_3.html “Phantom Loads”]
* {{usurped|1=[https://web.archive.org/web/20081202051746/http://www.planetark.com/dailynewsstory.cfm/newsid/49257/story.htm EU States Endorse Steps to Cut Standby Power Use]}}

{{DEFAULTSORT:Standby Power}}
[[Category:Electricity]]
[[Category:Energy conservation]]
[[Category:Environmental impact of the energy industry]]
[[Category:Electronics and the environment]]
[[Category:Electric power]]